The Spring Petclinic is the canonical reference sample application built with Spring Boot and Thymeleaf, demonstrating best practices in building Spring-based web applications; forks also exist showcasing implementations with modern architectures like microservices, reactive stacks, and AI integrations. In its default configuration, Petclinic uses an in-memory database (H2) which gets populated at startup with data. The h2 console is exposed and it is possible to inspect the content of the...